The Crișul Negru (Romanian), (Hungarian: Fekete-Körös) is a river in western Romania (Transylvania) and south-eastern Hungary (Békés county). The river starts at the confluence of headwaters Crișul Poienii and Crișul Băiței in the western Apuseni Mountains. It flows through the towns Ștei and Beiuș in Romania. One its tributaries is the small Roșia River. Crossing the border of Hungary the river, now called Fekete-Körös, joins the Fehér-Körös a few kilometres north from Gyula to form the Körös river. Part of the water from the river Crișul Repede is diverted towards the Crișul Negru by the Criș Collector Canal.